Menstrual cup



FIG. 1 is a left side elevational view of a menstrual cup, showing my new design, with all other sides being identical thereto;

FIG. 2 is a right side elevational view thereof;

FIG. 3 is a bottom plan view thereof; and

FIG. 4 is a top plan view thereof. 

The ornamental design for a menstrual cup, as shown and described. 